The first step is to assess your shoulder mobility. Try this common test of functional movement:

Stand with your feet flat on the floor and hold a PVC pipe directly overhead. Now, descend into an overhead squat. Optimal mobility, for which the highest score would be given on this movement, occurs when you can keep the bar over your feet, maintain heel contact with the floor and have your hips descend below horizontal level of the hip joint. In those with compromised mobility, the heels may rise or the PVC pipe may move either too far forward or stay too far behind the body; both positions are problematic and indicative of a shoulder-mobility limitation.

If your shoulder mobility is compromised, you should embark on a sustained program to increase shoulder range of motion. Don't labor under the impression that your shoulders can't increase in mobility -- the tissues limiting mobility can be stretched. It simply takes a sustained, intentional and smart program, along with effort on your part.

Proper Mechanics for Overhead Movements

Even though I am a proponent of training overhead, it's vital to understand the proper mechanics of the movements so as to minimize stress on the rotator cuff. Overhead exercises should be performed in such a way that the head of the humerus an maintain its proper position in the glenoid fossa.

This is best accomplished when you start the exercise from the "rack" position (across the front of your shoulders). It's also best to use your legs and perform overhead movements (to the extent you can) from a standing position with the exercise initiated by the legs, as in a push press or jerk.

To maintain proper biomechanics for rotator cuff protection, ensure that the bar follows a pathway that moves in a slight arc in front of your body, around your face as the chin is tucked back slightly (don't throw your head back), and ending with your arms fully extended overhead and in line with your ears. Avoid leaving your arms in front at the end of the movement, as such a finishing position places undue stress on the rotator cuff.

Finally, be very careful of rotator cuff fatigue. Remember, these muscles are small and tire out with repeated activity. Be vigilant about how much volume is included in workouts that feature multiple overhead sets. When rotator cuff muscles fatigue, the humeral head begins to migrate away from the glenoid because of the strong pull of the deltoids, and the likelihood of injury increases sharply.

Strengthening Your Overhead Movements

The final step is to train specific exercises that will help you develop overhead strength and stability in overhead movements. Here are three great exercises that will do just that.

Kettlebell Turkish Get-Up

The Turkish Get-Up is a fantastic exercise to improve overhead movements for two reasons. First, it helps increase strength through a large range of motion and across multiple planes of movement. Second it's superb for developing mid-line and core stability, which further transmits rigidity to movements overhead.

"I would have thought the perfect turkish getup would at least include a fez"

The comments aren't always simply hater on Youtube.

To perform, lie on the floor and, holding a kettlebell in your right hand, safely move the kettlebell into a locked-out position over your upper chest. Your right knee should be flexed with your foot flat on the ground and your heel near your buttocks, and your left leg should be straight and slightly abducted (away from your body). Perform a slight crunch to maneuver up by rolling onto your left hip and elbow. Think of punching your elbow down to the floor. Immediately following the crunch and punch, drive down hard with your right heel and push up onto your left hand, all while threading your left leg underneath you into a kneeling position. At this point, your left knee and right foot should be on the floor and the kettlebell should be locked out overhead. From this position, tighten your core and lunge forward to a standing position. Reverse these steps to return to the start position. Repeat on the other side.

During both the ascent and descent in the Turkish Get-Up, work hard to keep your right arm locked out overhead. You'll expend more energy and fatigue more quickly flexing your elbow even slightly and re-locking it. Also, keep your eyes focused on the kettlebell; this will keep your active shoulder properly aligned for overhead stability and strength.

Note: The verbal explanation of this exercise makes it out to be much harder and more complicated than it actually is. The best approach is to get down on the ground and start practicing it.

Behind-the-Neck Overhead Press with Snatch Grip

Step up to a rack and, with your hands at snatch width on the bar, position yourself underneath it with the bar on the back of your shoulders, as you would for a squat. With your feet at shoulder width, and without assistance from your lower body, perform a strict press upward and lock out at the top. Remember to squeeze your buttocks and abdominals so your hips stay underneath you and your core maintains rigidity. Return the bar slowly to the back of your shoulders.

Because this isn't a push press or a jerk, the motion should be SLOW AND CONTROLLED. As a strength-building exercise (providing the basis for more power and endurance), this movement should be performed between the repetition maximum ranges of three to six. This means that you should rarely perform high-rep presses if your goal is to build strength overhead. An occasional one-rep maximum is a good idea as well, to improve your progress with this grip and position overhead.

The use of forced reps should be consistent here if possible, with a spotter standing behind you and assisting at your elbows only at your sticking point. The spotter can also help lower the bar to your shoulders when the weight is in the 1RM to 3RM range.

Overhead Shrug

In a power rack, place a weight (slightly heavier than one with which you can successfully perform a push jerk) at a height about two inches above your head. Make sure the rack is stable, with a god metal catcher holding the weight. Facing the bar, grasp it with your hands at a clean width and bend at your knees to position your body directly under the bar with your arms locked out and shoulders tight. Make sure to maintain a solid core. Slowly and carefully straighten your legs; stand up under the weight, keeping our elbows locked out. As you do, the bar may slide up the rack. That's fine as long as your arms stay straight and you move the bar away from the rack to an overhead position once you're completely rigid under the bar.

Next, while holding the bar overhead and locked out, elevate and depress your shoulder girdle slowly and completely three times. You're essentially performing a shoulder shrug with this heavy overhead bar. Don't bend your elbows or even move at the wrists; just shrug your shoulders.

This exercise increases shoulder-girdle stability and will keep the bar from moving forward through "soft shoulders" in movements like the overhead squat and jerk. In other words, it enables more force production in "active shoulders" to keep them active. As a high-intensity exercise, lockouts should be performed judiciously and not programmed too frequently. And they should always be done with weight that exceeds your push-jerk 1RM.